Over the years, engineers have become more successful in reducing static leakage within common rail fuel systems. Reducing static leakage can improve performance, and efficiency, but is difficult to accomplish given the multitude of potential leak paths between the high pressure pump, common rail and valves within a plurality of fuel injectors for a common rail fuel system. While low static leakage is desirable, there is also a desire that all of the wetted volumes within a common rail fuel system return to atmospheric or tank pressure after the system is shutdown so that the risk of fuel spraying out of the system during servicing is reduced. While it is almost inconceivable that a common rail fuel system could be manufactured that had absolutely zero static leakage, the leakage in current systems may be so small that the decay of pressure in the high pressure volume can take an unacceptably long time to occur. Pressure decay times in excess of several minutes might be deemed unacceptable in the industry.
The present disclosure is directed toward one or more of the problems set forth above.